Long-term management of chronic spontaneous urticaria with omalizumab.

BACKGROUND

Clinical trials have shown the efficacy of omalizumabs efficacy in refractory chronic spontaneous urticaria (CSU) and chronic inducible urticaria (CIndU), but real-life management strategies are lacking.

AIM

To assess the long-term efficacy and safety of omalizumab, and to identify predictive factors and optimum dosage regimens.

METHODS

This was a prospective study of 13 patients (11 women, 2 men) with severe CSU [weekly urticaria activity score (UAS7) > 28] resistant to anti-H1 antihistamines. Patients were started on omalizumab 150 mg subcutaneously every 4 weeks. Dose and interval between administrations were adjusted according to clinical response (189 administrations; treatment duration range 2-38 months).

RESULTS

Mean UAS7 was 36.3 ± 5.4. Of the 13 patients, all had experienced angio-oedema, while in addition, 7 had delayed pressure urticaria (DPU) and 1 had solar urticaria (SU). After omalizumab treatment, 4 (30.8%) of the 13 patients had complete response (CR), and the remaining 8 (61.5%) had partial response. CR was achieved with a dose of 150 mg every 4 (n = 2 patients) or 5 (n = 2) weeks. One of these patients remained disease-free after stopping treatment. Partial responses were achieved with 150 mg every 4 weeks (n = 4) and with 300 mg (n = 4) at intervals of 5 weeks (n = 1), 4 weeks (n = 2) or 3 weeks (n = 1). Only one patient (7.7%) did not show significant improvement, despite a dose of 300 mg every 4 weeks. There were no significant differences in epidemiological, clinical and laboratory data between the different response groups. Only two adverse events were observed: one was mild headache and the other was severe angio-oedema and aggravation of urticaria within 6 h of omalizumab administration.

CONCLUSION

Omalizumab dose and interval between administrations could be individualized for long-term management of CSU.